Improved metallic pavement



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IMPROVBD METALLIC PAVEMENT.

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TO ALL WHOM IT MAY CONCERN:

Be it known that I, JOHN B. TARR, of Chicago, in the county of Cook, andState of Illinois, have invented a new and improved Metallic Pavement;and I do hereby declare that the following is a full, clear, and exactdescription thereof, reference beinglhad to the accompanying drawings,making a part of this specification,

in which Figurel is aperspeetive view ofltwo slabs of the metallicpavement put together.

Figure 2 is a toprviewY showing several slabs put together.

Figure' 3 is an edge view ot' onegof the slabs.

Figure 4 is a view showing apavement applied over an archway.

Similar letters of refercncendicatc corresponding parts in the severalfigures. v

This invention relates to an limprovement in the construction ofmetallic pavements for streets, sidewalks, halls, vaults, and for otherpurposes, where pavements are required. The object of my invention is toconstruct a metallic pavement of sections or slabs in such manner thatwhen laid down one section or slab will support, as well as lirmly holddown in place, those slabs which are adjacent to it without the use ofbolts, rivets, or

-other'fastenings than are aiorded by the slabs themselves, as will behereinafter described.

To enable others skilled in the art to understand my invention, I willdescribe its construction and operation.

In the accompanying drawings, iig. I is a perspective View of a portionof a pavement, the surfaces ofv thc slabs composing which are smoothivvIn figs. 2 and 3 I have shown a pavement which is more particularlyvdesigned for streets, it. having the surfaces of its slabs scoreddiagonally, so as to present projections for the purpose ofaffording-foothold for horses. These projections may be of the formrepresented, or ot' any other suitable form. Each slab A is'constructedof a rectangular form, either oblong or square, with'rectangular lipsaprojecting from its corners, and also with intermediate steps ordepressions Zn in two of its edges; which latter are made so as toreceive,I each, two of the corner projections a in laying'down thepavement, as Shown in tig. 2. The depressions b b, which are'in themiddle of the lengtliot' each slab A, receive theprojectionsof fourslabs. The dep'th of the depressions b 11 is equal to the thickness ofthe projections a a, so that when thc slabs are put together theirupper'surfaces will be tlush'with each other and perfectly level.' Itwill be seen by reference to figs. l and 2 that the slabs are puttogether so as to break joints with each other, and also so that theProjecting corners of euch slab t snugly into the intermediatedepressions of two slabs, thus the slabs are not only held down in placewithout the use of separate fastenings. By thus forming the slabs theywill be preventedfrom sinking, should the earthv beneath them settleandcease to aiord them support. I prefer to produce these slabs A ot' caststeel by casting this metal in metallic moulds, and,l while the metal isin a melted state, to subject it to great pressure for the purpose ofexpelling the air from it, and rendering it tougher andA more dense, sothat the slabs will not be liable to break easily. By casting the slabsin this way they can all be made of a uniform size, and tted togetherstrongly; and it will be found that the knobs or projections on theirsurfaces will' be chilled andv hardened so as' to be durable. I do notconfine my invention to cast-steel slabs constructed as above described,as the slabs can bc made of cast iron, or even of wrought `iron. I contemplate employing the self-locking slabs 'fox-'vault covers, andcasting themwith openings for receiving plates of glass for allowinglight to pass through them. Y

Having thus described my invention, what I claim as new, and desire-tosecure by yLetters Patent, is

The metallic-slabs A, constructed with Yinterlocking projections anddepressions, substantially as described.

JOHN B. TARE.

Witnesses:

Enw. SCHAFER, -Hsnnr SYLVESTER.

